Method for facilitating the separation of nitroglycerin.



RU'DOBF WEYEL, 0F BfiRRIGERHEIDE, GERMANY, ABSIGNO R, BY MESNE ASSIGNMEN T0 RHEIINISGEEE DYNAMITFABRIK, 0F COLOGNE, GERMANY.

itinrnon FOR FACILITATING THE snrens'rion or nrrn'ocnronnm.

No Drawing.

have been used for the manufacture of the same, thereby minimizing the element of danger Which is present in the separation. It has been proposed to add certain substances during the production of the nitroglycerin in order to facilitate the separation of the nitroglycerin, the substances sug gested being paraffin oil, hydrofluoric acid or fluoride and soluble silicates of the alkalis or alkaline earths. The use of paraffin oil is, however, disadvantageous inasmuch as an undesirable mud is formed on the surface of the nitroglycerin in the separating tank, and on the glasses in the second separation. For these reasons paraffin oil is only used in the cases where the degree of separation has been exceedingly poor. The use of soluble silicates of the alkalis or alkaline earths has been found to be not entirelyetfective as soluble silicates retard the separation owing to their emulsifying character. In the manner in which hydrofluoric acid and fluoride have been previously used to induce the separation of the nitroglycerin, these substances were used to remove the emulsified siliceous compounds present in the acids used for treating the glycerin, on

the theory that the presence of such siliceous compounds had a tendency to interfere with the rise of the nitroglycerin to the surface of the acids. It was therefore understood that the use 'of hydrofluoric acid or fluoride would be advantageous only in case of the presence of such siliceous compounds.

I have found that in those cases in which silica or siliceous compounds are absent, the addition of chemically pure sodium fiuorid or hydrofluoric acid is always inefiective, and that in all cases the best effect is obtained when care is taken to, produce a quantity of gaseous silicon fluorid by the presence of in 'oluble siliceous compounds.

specification of Letters latent.

Patented May 11, 11915 Application filed November 25,1912. serial 1%. teaser.

The production of gaseous silicon fluorid results in loosening the mixture and opening the Way for the rise of the nitroglycerin, which has a lower specific gravity than the acids used for producing the same, and the use of insoluble compounds of silica to producethesilicon fiuorid avoids any tendency to'ernuljsification which is present in the case of soluble silicon c'onipounds. Ga'e Way of causing the liberation of silicon fiuorid in this mariner is b adding to th'eacidsa mixture of sodium uorid and an insoluble sili= ceous compbund, such as silica or one of the insoluble silicates. The reaction which takes place is the K following Care should be taken to add the iluorid and siliceous"cinnpound at the proper for the reason that if they are added too soon the air agitation will drive off i con fiuorid before the formation of troglycerin, and if they are added too has there will not be sufiicient time to allow the 233 silicon fluorid to form. In carrying out the process it been found advantageous to mix sodium iiuorid with about 8 to 10% of its own Weight of fine, washed, light kieselguhr, and to add about 20 g. of this mixture to kg. of the glycerin at from five to six minutes before the end of the nitration. It will be found, in carrying out the process in this manner, that the time for the separation of the nitro- 91) g yc'erin will be about one-third of its normal duration.

It will be understood that the process may be carried out in man different Ways so long as the same result is obtained. Instead of utilizing a mixture of iiuorids and a siliceous compound other substances may be used which will be acted upon by acids similarly to liberate silicon fluorid. One substance of this character which may be 100 used is sodium fluosilicate. In carrying out my invention with this compound, the reaction is as follows:

Na SiFl +H S0 =SiFl +Na SO,-i-2Ill l.

In using sodium .fiuosilicate, from 10 to 15 g. thereof should be added to 100 kg. of glycerin. It will be noted that in this reacto the sodium fluosilicate about 10% of silica, preferably in the form of kieselguhrl When using silica with. the sodium fluosilicate, even a smaller quantity of the materials 'may be added to bring about the separation of the nitroglycerin in the same period of time.

"While I have described my invention above in detail, I wish it to be understood that many changes may be made therein Without departing from the spirit thereof.

1 claim: a

l. The method of facilitating the separation of a mixture of liquids containing nitroglycerin and an acid, which comprises generating silicon fluorid in said liquids by the addition of a fluosilicate.

2. The method of facilitating the separation of a mixture of liquids having diiferent specific gravities, containing nitroglycerin and an acid, which comprises generating silicon fluorid in said liquids by the addition of a fluosilicate. i

3. The method of facilitating the separar tion of a mixture of liquids containing nitro glycerin and an acid, which comprises generating silicon fluorid in said liquids by the addition of a fluosilicate and siliceous compound. V

4. The method of, facilitating the separa tion of a mixture of liquids. having difi'erent specific gravities containing nitroglycerin 'and an acid, which comprises generating silicon fluorid in said liquids by the addition of a fluosilicate and siliceous compound.

5. The method of facilitating the separation of a mixture of liquids containing nitroglycerin and an acid which comprises generating silicon fluorid in said liquids by the addition of sodium fiuosilicate.

6. The method of facilitating the separation of a mixture of liquids containing nitro-- glycerin and an acid which comprises gener ating silicon fluorid in said liquids by the addition of sodium fluosilicate' and silica.

7. The method of facilitating the separation ofa mixture of liquids Containing nitroglycerin and an acid which comprises generating silicon fluorid in said liquids by the addition ofsodium fiuosilicate and kieselr. In testimony that I claim the foregoing I have hereunto set myahand. RUDOLF WEYEL. Witnesses:

CHAS. VANDORY, KARL KNABP, 

